Fiber reinforced cementitious compositions containing hydraulic cement, inorganic mineral fillers and pozzolans as well as chemical additives like plasticizers and water dispersants have been used in the construction industry to form the interior and exterior walls of residential and/or commercial structures. However, a drawback of such conventional panels is that they do not have sufficient compressive strength to provide a high degree of resistance to ballistic and blast loads.
Current practice for producing ultra-high strength cementitious compositions relies upon efficient particle packing and extremely low water dosage for achieving ultra-high material strength. As a consequence of the raw materials utilized to achieve dense particle packing and the extremely low water usage in these compositions, the cementitious mixtures have extremely stiff rheological behavior with dough like consistency in the freshly mixed state. The stiff consistency makes these mixtures highly unworkable and extremely difficult to process in conventional manufacturing processes for making thin cement-based products and composites.
U.S. Pat. No. 4,158,082 A to Belousofsky discloses a laminated cement based structure with a fiber glass skin that is impact resistant and may use Portland based cements.
U.S. Pat. No. 4,948,429 A to Arfaei discloses a cementitious composition containing portland cement, sand, fumed silica and a polyether.
U.S. Pat. No. 4,793,892 to Miller et al., incorporated herein by reference in its entirety, disclose an apparatus manufacturing a concrete panel with a light weight cement core containing Portland cement and fiber glass scrim facing which is adhesively bonded to the surfaces of the cement core.
U.S. Pat. No. 4,434,119 to Teare disclose the application of two layers of scrim to a cement panel and then a thin layer of slurry is then applied to the top of the panel before the surface is screed. Teare uses a paper skin layer over the surface of the cement panel between adjacent panels during curing and this paper layer is subsequently removed for the final cement panel product.
U.S. Pat. No. 5,997,630 to Angelskar discloses TEA and tartaric acid.
U.S. Pat. No. 6,176,920 to Murphy discloses a method of method for constructing a cementitious panel of multiple layers utilizing a smoothing head, shearer and screeding process.
U.S. Pat. No. 6,119,422 B1 to Clear discloses an impact resistant strong structural cementitious building panel with outer facing of fiberglass reinforcing mesh where the composite cementitious has an aggregate core with inner and outer faces of fiberglass mesh.
U.S. Pat. No. 6,309,457 B1 Guerinet et al. discloses a self-leveling cement composition that includes Portland cement, silica sand of maximum 10 mm size or 0-5 mm size, or a blend of 0-0.4 mm and 0-5 mm size; fine mineral aggregates such as fly ash or silica flour having dimensions of less than 200 microns, preferably less than 100 microns; a first plasticizer which is a water-soluble or water-dispersible organic compound containing at least one aminodi(alkenephosphonic) group; and a second water-soluble or water-dispersible plasticizer which is of the polycarboxylic acid type and contains polyether chains. Example 1 indicates a compressive strength in 28 days of 32 MPa (about 4600 psi).
U.S. Pat. No. 6,437,027 to Isomura et al. discloses a cementitious composition containing portland cement, silica sand of less than 5 mm size; and polycarboxylate polyether of 0.01-2.5 wt. %.
U.S. Pat. No. 6,849,118 B2 to Kerkar et al. discloses a cementitious composition containing Portland cement, silica sand of 0 to 6 mm size; and polycarboxylate (ADVA® Cast plasticizer).
U.S. Pat. No. 6,858,074 B2 to Anderson et al. discloses a cementitious composition containing portland cement, silica sand, fumed silica, accelerator, retarder, and polycarboxylate high range water reducing dispersant.
U.S. Pat. No. 6,620,487 to Tonyan et al., incorporated herein by reference in its entirety, discloses a reinforced, lightweight, dimensionally stable structural cementitious panel (SCP's or SCP panels) capable of resisting shear loads when fastened to framing equal to or exceeding shear loads provided by plywood or oriented strand board panels. The panels employ a core of a continuous phase resulting from the curing of an aqueous mixture of calcium sulfate alpha hemihydrate, hydraulic cement, an active pozzolan and lime, the continuous phase being reinforced with alkali-resistant glass fibers and containing ceramic microspheres, or a blend of ceramic and polymer microspheres, or being formed from an aqueous mixture having a weight ratio of water-to-reactive powder of 0.6/1 to 0.7/1 or a combination thereof. At least one outer surface of the panels may include a cured continuous phase reinforced with glass fibers and containing sufficient polymer spheres to improve nail ability or made with a water-to-reactive powders ratio to provide an effect similar to polymer spheres, or a combination thereof.
U.S. Pat. No. 6,875,801 B2 to Shendy et al. discloses a cementitious composition containing portland cement, sands, fumed silica and polycarboxylate of 0-2 wt %.
U.S. Pat. No. 6,942,727 B2 Daczko et al. discloses a high early strength cementitious member that includes Portland cement; fine aggregate such as silica sand, the fine aggregate are materials that almost entirely pass through a Number 4 sieve, coarse aggregate such as sand, the coarse aggregate are materials predominantly retained on a Number 4 sieve); silica fume pozzolan; 0.025-0.7% polycarboxylate dispersant based on dry weight of cement; and structural synthetic fibers. The cementitious member can be used to make wall panels. The cementitious member can exhibit 24 hour compression strength greater than 10,000 psi; however these compositions do not contain a pozzolan.
U.S. Pat. App. Pub. 2002/0004559 to Hirata et al. discloses a cementitious composition containing portland cement, sands, fumed silica and polyethers of more than 0.5% wt. e.g. 2 wt. %.
U.S. Pat. App. Pub. No. No. 2004/0149174 to Farrington et al. discloses a cementitious composition containing portland cement, sands, fumed silica and polycarboxylate of 0.01-0.2 wt %.
U.S. Pat. App. Pub. No. 2004/0198873 to Bury et al. discloses a cementitious composition containing portland cement, silica sand, fumed silica and polycarboxylate of 0.02-2 wt %
U.S. Pat. App. Pub. No. 2004/0211342 to Sprouts et al. discloses a cementitious composition containing portland cement, silica sand, fumed silica and polycarboxylate of 0.1-2 wt %
U.S. Pat. App. Pub. No. 2004/0231567 to Dulzer et al. discloses a cementitious composition containing portland cement, sand, fumed silica and polycarboxylate of 0.1-10 wt % of the total dry cementitious binder.
U.S. Pat. App. Pub. No. 2005/0239924 to Lettkeman et al. discloses a cementitious composition containing portland cement, fine sands, fumed silica and polycarboxylate of 0.05-2.5 wt %.
U.S. Pat. App. Pub. No. 2005/0274294 to Brower et al. discloses a cementitious composition containing portland cement, fine sands, fumed silica and polycarboxylate of 1-4% wt.
U.S. Pat. App. Pub. No. 2006/0281836 to Kerns et al. discloses a cementitious composition containing portland cement, fine sands, fumed silica and polycarboxylate.
U.S. Pat. App. Pub. No. 2006/0174572 to Tonyan et al., incorporated herein by reference, discloses non-combustible reinforced cementitious lightweight panels and metal frame system for shear walls.
U.S. Pat. App. Pub. No. 2007/0125273 to Pinto discloses a cementitious composition containing portland cement, fine sands, fumed silica and polycarboxylate such as 1-2 wt. %.
U.S. Pat. App. Pub. No. 2007/0175126 to Tonyan et al., incorporated herein by reference in its entirety, disclose a structural cementitious panel made with cores containing lightweight fillers like hollow spheres which is much lighter than the cementitious armor panels of the present invention which contain sand as inorganic fillers for blast resistance.
U.S. Pat. App. Pub. No. 2007/0228612 A to Durst et al, incorporated herein by reference discloses blast resistant concrete also suitable for limiting penetration of ballistic fragments.